A sound generating apparatus is an apparatus capable of converting an electric signal into a sound signal. The sound generating apparatus includes, for example, a receiver. For example, a moving-coil receiver and a loudspeaker may be called receivers. The sound generating apparatus is widely applied in a media device. For example, the media device includes, for example, a mobile phone and an earphone thereof.
A high-frequency performance is an important performance of the sound generating apparatus. In general, a frequency response curve of the moving-coil receiver will drop rapidly within a range of 6 kHz to 9 kHz. The frequency response curve of a typical loudspeaker will also drop after tens of kilohertz. In other words, the frequency response curve of the sound generating apparatus will have a high-frequency cut-off frequency. With the development of technologies, requirements for the high-frequency cut-off frequency of the sound generating apparatus are getting higher and higher. However, due to limitations of materials and a production process of the sound generating apparatus, in particular limitations of materials and a production process of the moving-coil receiver, the high-frequency cut off frequency of the sound generating apparatus is difficult to increase.
With the wide application of 4G communications, it is required to have the sound generating apparatus equipped with an ultra-wide frequency band. For example, in some cases, the high-frequency cut off frequency of the sound generating apparatus is required to reach above 16 kHz. However, for example, it is very difficult to reach this requirement for a common moving-coil receiver.